Electric rotary brush module

ABSTRACT

An electric rotary brush module for external use at the mouth or entrance of a vacuum cleaner, comprising a casing having an inlet and an outlet and an internal passage extending from the inlet through to the outlet. The outlet is adapted for detachable connection to the entrance of the vacuum cleaner for communication therewith. A brush is supported for rotation in the passage within the inlet. The brush protrudes slightly outwardly from the inlet. An electric motor is located within the casing for rotating the brush.

[0001] The present invention relates to an electric rotary brush module for use on a vacuum cleaner.

BACKGROUND OF THE INVENTION

[0002] There are various types of vacuum cleaners available on the market, including portable cleaners, upright domestic floor cleaners and powerful industrial cleaners, etc. Vacuum cleaners can typically be classified, according to their applications, into dust cleaners and water cleaners as well as dust-and-water cleaners. Alternatively, they may also be classified into cleaners that incorporate a built-in rotary brush and cleaners that are provided with a detachable rotary brush.

[0003] Manufacturers supply various add-on accessories to expand the function, or use, of vacuum cleaners. For example, with the use of an extension pipe, a vacuum cleaner can gain access to a narrow or confined space. A brush enables a vacuum cleaner to clean fabric curtains. When provided with a rubber-sponge end piece, a vacuum cleaner can also be used to collect water or liquid.

[0004] The invention seeks to expand the function of a vacuum cleaner by providing an electric rotary brush module.

SUMMARY OF THE INVENTION

[0005] According to the invention, there is provided an electric rotary brush module for external use at the mouth or entrance of a vacuum cleaner, comprising a casing having an inlet and an outlet and an internal passage extending from the inlet through to the outlet. The outlet is adapted for detachable connection to the entrance of the vacuum cleaner for communication therewith. A brush is supported for rotation in the passage within the inlet. The brush protrudes slightly outwardly from the inlet. An electric motor is located within the casing for rotating the brush.

[0006] Preferably, the outlet of the casing has an external cross-section smaller than an internal cross-section of the entrance of said vacuum cleaner, for insertion into the entrance for connection thereto.

[0007] More preferably, the external cross-section of the casing outlet is marginally smaller than the internal cross-section of the entrance of said vacuum cleaner, such that the outlet is connectable to the entrance by function.

[0008] In a specific construction, the outlet of the casing comprises a sleeve projecting at an inclined acute angle backwards from an upper side of the casing.

[0009] It is preferred that the inlet of the casing has an opening that is substantially flat and is oblong in a direction transverse to that of the passage.

[0010] In a specific construction, the casing comprises an upper shell including the outlet and a lower shell including the inlet, said upper and lower shells being secured together to form the casing.

[0011] Preferably, the brush has an axis of rotation extending across an or the opening of the casing inlet in a direction transverse to that of the passage.

[0012] More preferably, the brush has a body comprising a spool.

[0013] Preferably, the brush has a body supported by at least one co-axial pin for rotation about the pin.

[0014] Preferably, the brush has a body and includes tufts of bristles that are arranged in a substantially helical manner along the length of the body.

[0015] In a preferred embodiment, the brush and the motor are arranged to have respective axes that are parallel to each other, and drive transmission means is provided between the motor and the brush for transmitting the drive of the motor to the brush.

[0016] Preferably, the drive transmission means is speed reducing.

[0017] More preferably, the drive transmission means comprises a relatively smaller circular member mounted fast on a shaft of the motor, a relatively larger circular member fixed to the brush about its axis of rotation, and a belt disposed in engagement around the two circular members.

[0018] It is preferred that the motor has a pair of terminals connected to an electrical connector for connection to an external power source.

[0019] It is further preferred that the electrical connector is located at an outer surface of the brush module casing, and the brush module includes a separate cable having opposite ends connectable to the electrical connector and an external power source respectively.

[0020] The invention also provides a combination of the aforesaid electric rotary brush module and a vacuum cleaner having a entrance at which the brush module is adapted for external connection and use.

[0021] The invention also provides a combination of the aforesaid electric rotary brush module and a vacuum cleaner having a entrance at which the brush module is adapted for external connection and use. The vacuum cleaner has a body housing an electric motor for operating the vacuum cleaner. The motor has a pair of terminals connected to an electrical connector located at an outer surface of the body. To this connector the electrical connector of the brush module is connectable externally by means of a separate cable such that the two motors of the brush module and vacuum cleaner are connected in parallel together.

[0022] Preferably, the vacuum cleaner includes an electrical switch for controlling the operation of its motor as well as the motor of the brush module when the two motors are connected in parallel together.

BRIEF DESCRIPTION OF DRAWING

[0023] The invention will now be more particularly described, by way of example only, with reference to the accompanying drawing, which is an exploded perspective view of an embodiment of an electric rotary brush module in accordance with the invention and a vacuum cleaner using the module.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0024] Referring to the drawing, there is shown an electric rotary brush module 100 embodying the invention, which is adapted for use with a hand-held vacuum cleaner 200 suitable for use in a car, truck or boat or at home, etc. The vacuum cleaner 200 has a body 210 and a nozzle 230 releasably connected to the front end of the body 210. The body 210, which is assembled by securing left and right shells 212 together by screws, has at its top rear end a ring portion that acts as a handle 214. The body 210 includes a central opening 216 at its front end wall for intake of air, said opening 216 being covered by an integrally formed grille 217, and a series of vent slots 218 on each of its opposite side walls or the shells 212.

[0025] Inside the cleaner body 210, a centrifugal fan 220 is supported, at a position immediately behind and in alignment with the air intake opening 216, for rotation through direct drive by an electric motor 222. In operation, the motor 222 rotates the centrifugal fan 220 to create a suction that draws air into the body 210 through the opening 216 and expels the air out through the vent slots 218.

[0026] The motor 222 has a pair of terminals 223 which are connected, via an electrical slide switch 224 located on the handle 214, to a power cord 226. The power cord 226 extends out at the rear end of the body 210 and terminates at an electrical plug 227 for a cigarette lighter socket in a car and hence connection to the car battery. An electrical socket 228, which is located at the outer surface of the rear end of the body 210, is connected in parallel across the terminals 223. The switch 224 serves to turn on or off the motor 222 and, at the same time, to enable or disable the socket 228.

[0027] The nozzle 230 tapers forwards into a wedge-shaped front end that is formed on its bottom surface with a flat and oblong entrance 231. The entrance 231 has an inner end that is normally closed by a flap 229, together forming a one-way flap valve to permit entry but not exit through the entrance 231. An open rear end 232 of the nozzle 230 matches and covers the entire front end wall of the cleaner body 210.

[0028] A lid 233 that extends internally across the rear end 232 of the nozzle 230 closes that end. The nozzle end 232 has short protrusions on its inner surface. The lid 233 is of matching shape and size such that it can be pressed into the nozzle end 232 and then snapped fitted by the protrusions in place, and can subsequently be detached. The lid 233 includes a central opening 234 and a frusto-conical frame 235 that is located on the inner side of the lid 233 around the opening 234. The frame 235 is enclosed by a replaceable fabric filter bag 236 which has an elastic rim 237 stretched within an annular groove around the base of the frame 235.

[0029] The front end wall of the cleaner body 210 is provided with an upper spring-loaded hook 238 and a lower fixed groove 239 facing each other. The hook 238 and groove 239 are arranged to engage, and thus connect, the nozzle 230 by the upper and lower edges of its rear end 232 respectively. While the nozzle 230 is connected, the central opening 234 of its lid 233 is aligned and coupled with the air intake opening 216 of the cleaner body 210.

[0030] This results in communication between the interiors of the cleaner body 210 and the nozzle 230, such that the suction created by the motor-driven fan 220 inside the body 210 takes effect through the nozzle 230 at the nozzle entrance 231. The filter bag 236 finds support from the frame 235 and serves to filter and thus block off dust or the like from the air drawn in through the nozzle 230 into the body 210. The dust will be collected in the nozzle 230, and can be disposed later by removing the lid 233.

[0031] The nozzle 230 may be extended by means of an elongate pipe 240, which has a brush 242 at its free end, inserted into the entrance 231, as generally known in the art.

[0032] Referring now to the electric rotary brush module 100, it has a casing 110 assembled by securing upper and lower shells 112 and 114 together by screws. The casing 110 has an inlet in the form of a generally flat opening 120 in the bottom wall of the lower shell 114, and an outlet in the form of a generally flat sleeve 130 that projects at an inclined acute angle backwards integrally from the top wall of the upper shell 112. An internal passage is defined by the casing 110, which extends from the opening 120 through to the sleeve 130. The opening 120 is oblong in a direction transverse to that of the passage.

[0033] The outlet sleeve 130 has an external cross-section marginally smaller than the internal cross-section of the entrance 231 of the cleaner nozzle 230 such that it can be inserted into the entrance 231 and connected therein by friction, and can later be detached. While the sleeve 130 is connected, the interior of the module casing 110 communicates with that of the nozzle 230 and in turn that of the cleaner body 210. Thus, the suction created in the cleaner body 210 is applied through the nozzle 230 and then the module casing 110 at the inlet opening 120.

[0034] The brush module 100 includes a generally cylindrical brush 140 which is supported for rotation in the passage within the inlet opening 120 about an axis of rotation that extends across opposite ends of the opening 120 in a direction transverse to that of the passage. The rotary brush 140 comprises a spool 142 as its body, a pair of co-axial pins 144 projecting out from opposite ends of the spool 142, and tufts of bristles 148 planted in the shaft of the spool 142.

[0035] The pins 144 are supported by corresponding bearings 146 which are clamped on opposite left and right sides between the upper and lower shells 112 and 114, whereby the spool 142 is rotatable about the pins 144. It is clear that the two pins 144 may be replaced by a single longer pin that acts as a shaft passing co-axially through the entire spool 142. The tufts of bristles 148 are arranged in a generally helical manner and at regular positions along the length of the spool 142. The bristles 148 protrude slightly outwardly from the inlet opening 120, such that they can just reach the surface to be cleaned.

[0036] The brush module 100 further includes an electric motor 150 located within the casing 110 for rotating the brush 140. The motor 150 has a shaft 152 that extends parallel to the axis of the brush 140, on which shaft 152 a cylindrical pinion 154 is mounted fast. The end of the spool 142 of the brush 140 adjacent the pinion 154A is fixed with a co-axial pulley 156. A toothed belt 158 is disposed in engagement around the pinion 154 and pulley 156. The pinion 154 has a diameter considerably smaller than that of the pulley 156, such that the two members and the belt 158 together constitute a drive transmission system for transmitting the drive of the motor 150 to the brush 140 at a reduced speed.

[0037] The motor 150 includes a pair of terminals 151 which are connected in parallel to an electrical socket 153 for connection to an external power source. The socket 153 is located at an outer surface of the module casing 110. An external separate power cable 160 is used, which has a pair of power plugs 162 at opposite ends for insertion into the present socket 153 and the earlier socket 228 of the vacuum cleaner 200 respectively.

[0038] With the use of the cable 160, the motor 150 of the brush module 100 is connected in parallel to the motor 222 of the vacuum cleaner 200. Both the brush module 100 and the vacuum cleaner 200 can then be connected to the same external power source, i.e. the car battery, and be controlled by the same switch 224 on the handle 214 of the vacuum cleaner 200.

[0039] The invention has been given by way of example only, and various other modifications of and/or alterations to the described embodiment may be made by persons skilled in the art without departing from the scope of the invention as specified in the appended claims. 

1. An electric rotary brush module for external use at the entrance of a vacuum cleaner, comprising a casing having an inlet and an outlet and an internal passage extending from the inlet through to the outlet, said outlet being adapted for detachable connection to the entrance of said vacuum cleaner for communication therewith, a brush supported for rotation in the passage within the inlet, said brush protruding slightly outwardly from the inlet, and an electric motor located within the casing for rotating the brush.
 2. The electric rotary brush module as claimed in claim 1, wherein the outlet of the casing has an external cross-section smaller than an internal cross-section of the entrance of said vacuum cleaner, for insertion into the entrance for connection thereto.
 3. The electric rotary brush module as claimed in claim 2, wherein the external cross-section of the casing outlet is marginally smaller than the internal cross section of the entrance of said vacuum cleaner, such that the outlet is connectable to the entrance by function.
 4. The electric rotary brush module as claimed in claim 1, wherein the outlet of the casing comprises a sleeve projecting at an inclined acute angle backwards from an upper side of the casing.
 5. The electric rotary brush module as claimed in claim 1, wherein the inlet of the casing has an opening that is substantially flat and is oblong in a direction transverse to that of the passage.
 6. The electric rotary brush module as claimed in claim 1, wherein the casing comprises an upper shell including the outlet and a lower shell including the inlet, said upper and lower shells being secured together to form the casing.
 7. The electric rotary brush module as claimed in claim 1, wherein the brush has an axis of rotation extending across an or the opening of the casing inlet in a direction transverse to that of the passage.
 8. The electric rotary brush module as claimed in claim 7, wherein the brush has a body comprising a spool.
 9. The electric rotary brush module as claimed in claim 7, wherein the brush has a body supported by at least one co-axial pin for rotation about the pin.
 10. The electric rotary brush module as claimed in claim 7, wherein the brush has a body and includes tufts of bristles that are arranged in a substantially helical manner along the length of the body.
 11. The electric rotary brush module as claimed in claim 1, wherein the brush and the motor are arranged to have respective axes that are parallel to each other, and drive transmission means is provided between the motor and the brush for transmitting the drive of the motor to the brush.
 12. The electric rotary brush module as claimed in claim 11, wherein the drive transmission means is speed reducing.
 13. The electric rotary brush module as claimed in claim 12, wherein the drive transmission means comprises a relatively smaller circular member mounted fast on a shaft of the motor, a relatively larger circular member fixed to the brush about its axis of rotation, and a belt disposed in engagement around the two circular members.
 14. The electric rotary brush module as claimed in claim 1, wherein the motor has a pair of terminals connected to an electrical connector for connection to an external power source.
 15. The electric rotary brush module as claimed in claim 14, wherein the electrical connector is located at an outer surface of the brush module casing, and the brush module includes a separate cable having opposite ends connectable to the electrical connector and an external power source respectively.
 16. A combination of the electric rotary brush module as claimed in claim 1 and a vacuum cleaner having a entrance at which the brush module is adapted for external connection and use.
 17. A combination of the electric rotary brush module as claimed in claim 14 and a vacuum cleaner having a entrance at which the brush module is adapted for external connection and use, wherein the vacuum cleaner has a body housing an electric motor for operating the vacuum cleaner, said motor having a pair of terminals connected to an electrical connector located at an outer surface of the body, to which connector the electrical connector of the brush module is connectable externally by means of a separate cable such that the two motors of the brush module and vacuum cleaner are connected in parallel together.
 18. The combination as claimed in claim 17, wherein the vacuum cleaner includes an electrical switch for controlling the operation of its motor as well as the motor of the brush module when the two motors are connected in parallel together. 